1. Field of the Invention
The invention relates generally to keepers for idler rolls which lock the ends of a pair of adjacent rolls in fixed position within a bracket.
2. Description of the Prior Art
The desirability of providing a sturdy, inexpensive, easily insertable and removable device for retaining idler rolls in fixed position within a bracket has long been recognized. Several attempts have been made to realize these goals, although the most common approach has been to provide a resilient spring clip that is secured to the bracket and fits over the end cap of the idler roll to capture the roll within an aperture in the bracket. One particular clip configuration is disclosed in U.S. Pat. No. 3,157,272, granted Nov. 17, 1964, to James Bay.
The strength of such resilient clips, however, which make contact with the roll at a very limited area, is sorely limited, so that the vibrations encountered during transport of an idler roll assembly to a job site may cause the clip to spring out of locking position. Alternatively, the clip may be deformed and its strength and effectiveness further diminished. Also, two resilient clips are required for each roll, i.e., one clip for each end of the roll, and the insertion of a pair of clips into the closely spaced supports of an interior bracket of an idler roll set may prove to be difficult to accomplish.
Another common attempt to realize the goals set forth above has been to provide a rigid sheet metal clip having a planar body and a pair of depending legs. Ears or tabs are struck in the depending legs, and cooperating abutments are formed in the bracket adjacent to its upper end. The ends of adjacent rolls are positioned in the apertures in the bracket, and then the clip is forced downwardly over the caps until the ears and abutments interengage to lock the rolls in fixed position within the bracket. A representative clip configuration is disclosed in U.S. Pat. No. 2,843,432, granted July 15, 1958 to A. J. Kindig.
While one rigid clip can hold a pair of rolls in fixed position, and the rigid clip is thus better suited for use with the interior brackets on an in-line, idler roll assembly, such as used in a troughing conveyor, the clip disclosed in the Kindig patent necessitates the modification of existing brackets to form abutments thereon, or alternatively, the manufacture of new brackets with such abutments. Furthermore, the insertion and removal of such clips may be difficult where the vertical spacing between the underside of the conveyor belt and the upper end of the central bracket is limited.